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Shape of a liquid front upon dewetting

Ralf Seemann·Stephan Herminghaus·Karin Jacobs
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Abstract

We examine the profile of a liquid front of a film that is dewetting a solid substrate. Since volume is conserved, the material that once covered the substrate is accumulated in a rim close to the three phase contact line. Theoretically, such a profile of a Newtonian liquid resembles an exponentially decaying harmonic oscillation that relaxes into the prepared film thickness. For the first time, we were able to observe this behavior experimentally. A non-Newtonian liquid - a polymer melt - however, behaves differently. Here, viscoelastic properties come into play. We will demonstrate that by analyzing the shape of the rim profile. On a nm scale, we gain access to the rheology of a non-Newtonian liquid.

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Ralf Seemann, Stephan Herminghaus, Karin Jacobs. 2001-05-04. Shape of a liquid front upon dewetting. https://doi.org/10.1103/physrevlett.87.196101

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